We present a generalized Landau-Brazovskii theory for the solidification of chiral molecules on a spherical surface. With increasing sphere radius one encounters first intervals where robust achiral density modulations appear with icosahedral symmetry via first-order transitions. Next, one encounters intervals where fragile but stable icosahedral structures still can be constructed but only by ...

Binary compounds $A$Bi ($A$ = K, Rb, Cs) crystallize in P2$_1$/c structure containing both clockwise and anticlockwise chiral chains of Bi atoms. Electronic band exhibits the insulating nature these systems, with gap about $0.25$ eV. The presented study dynamical properties confirm a stability system symmetry. crystal contains quasi-one-dimensional chains, exhibiting four-fold-like rotational `...

OBJECTIVES/HYPOTHESIS The diagnosis of paresis in patients with vocal fold motion impairment remains a challenge. More than 27 clinical parameters have been cited that may signify paresis. We hypothesize that some features are more significant than others. STUDY DESIGN Prospective case series. METHODS Two laryngologists rated laryngoscopy findings in 19 patients suspected of paresis. The di...

Abstract A topological insulator Bi 2 Se 3 becomes a superconductor by doping Cu or Sr. Due to the nematicity of these x ( = Cu, Sr) materials, physical quantities show two-fold rotational symmetry as function in-plane magnetic field angle φ despite their three-fold structural in plane. In this study, single crystals Sr (0.0 ≤ 0.17) were grown self-flux method. Using crystals, extensive measure...

purpose: to report a young patient with microphthalmos associated with bilateral papillomacular fold and severe hyperopia case report: in this observational case report, a sixteen-year-old young man was referred with high hyperopia to al-zahra eye hospital, zahedan university of medicalf sciences, zahedan, iran, for check up. spherical error in right eye (re) was +14.75 d and in the left eye (l...

In this paper we are concerned with producing exhaustive lists of simple monotone Venn diagrams that have some symmetry (non-trivial isometry) when drawn on the sphere. A diagram is simple if at most two curves intersect at any point, and it is monotone if it has some embedding on the plane in which all curves are convex. We show that there are 23 such 7-Venn diagrams with a 7-fold rotational s...

In their AMW’14-paper, Frochaux, Grohe, and Schweikardt showed that the query containment problem for monadic datalog on finite unranked labeled trees is Exptime-complete when (a) considering unordered trees using the child-axis, and when (b) considering ordered trees using the axes firstchild, nextsibling, and child. Furthermore, when allowing to use also the descendant-axis, the query contain...

For each n ≥ 4 we show how to construct simple Venn diagrams of n curves embedded on the sphere with the following sets of isometries: (a) a 4-fold rotational symmetry about the polar axis, together with an additional involutional symmetry about an axis through the equator, and (b) an involutional symmetry about the polar axis together with two reflectional symmetries about orthogonal planes th...

The ionotropic glutamate receptors (iGluRs) represent a major family of ion channels whose quaternary structure has not yet been defined. Here, we present the three-dimensional structure of a fully assembled iGluR, determined at approximately 20A resolution by electron microscopy. Analysis of negatively stained single-particle images reveals the presence of 2-fold, but not 4-fold, symmetry for ...